A wide variety of tools for downhole applications are operated on supplied fluid pressure. One of the most common ways to supply hydraulic pressure to downhole components in a bottom hole assembly is to run a control line from the surface. A control line is secured outside a tubing string and connected at the surface to a source of fluid pressure and at the other end to a housing of a downhole tool. Generally, when pressure is applied from the surface through the control line it is communicated to the tool housing where it moves a piston that actuates the tool to perform a downhole operation. Subsurface safety valves commonly operate this way. They are designed to stay in the open position as long as control line pressure is applied. Applying pressure compresses a return spring acting on the flow tube. Applying pressure shifts the flow tube to rotate a flapper to hold the valve open. A loss of control line pressure allows the spring to return the flow tube up to allow the flapper to close generally under the further bias of a pivot pin mounted spring.
Other variations involve using internal tubing pressure applied form the surface. In these designs there is a ball seat that receives a ball. When the ball has landed pressure can be built up to actuate the tool. In some designs the ball on the seat can be blown out with a further increase in pressure beyond what it took to operate the tool so that the internal passage in the tool is at least partially cleared for running other tools even further into a well. These designs require special features and can shock a formation below when the ball and its seat are blown out or alternatively when the ball is blown through the seat.
Sometimes tools designed for one job are retrofitted to other jobs but require modification to function in the new application. For example downhole wet connects are devices that mate an upper portion of a string to a lower portion. These devices feature an orientation pin on one half of a connection and a longitudinal groove usually having a broad tapering entrance to initially grab the alignment pin and cause some relative rotation so that the two parts of the string can be mated downhole. Wet connects generally connect the main bores in the upper and lower tubular strings as well as connecting adjacent conduits for such purposes as a control line for a subsurface safety valve, for example. Once wet connect connections are fully mated, they generally need to be locked together and such locks or anchors have been in the past actuated with hydraulic pressure from an available adjacent control line that the wet connect mated to its downhole counterpart segment. However, some wet connects are not designed to couple hydraulic control lines so a ready source of hydraulic pressure was not available for such designs. One design that connected fiber optic cables had no available hydraulic sources but still needed to be locked in a connected mode. It was this need to adapt a known design for a new application that drove to the discovery of the present invention that not only solved the problem of locking that connection together but further has application in a wide variety of situations where hydraulic pressure is needed for a variety of purposes. In the fiber optic wet connect, for example, not only was hydraulic pressure needed to lock the connection together, but there was a need to clean the fiber cable ends of one or more cable end pairs before the connection was driven home to get drilling fluid or other solids that might impede signal transmission through the cable connection out of the way. The present invention addresses a problem in this context, in a preferred embodiment but its application is far more universal to a wide variety of tools. Variations are also possible to allow multiple pressure sources to deliver pressure to various locations with a single or multiple manipulations of the string. One time operation with a single string manipulation is envisioned as well as multiple actuations from a series of string manipulations with multiple reservoirs or reservoirs that can recharge for reuse. Details of these alternatives will be more readily apparent to those skilled in the art from a review of the description of the preferred embodiment and the associated drawing while recognizing that it is the claims that contain the full scope of the invention.